Hydrogenation of crotonaldehyde



Patented Jan. is, 1931 l ft,788,896

UNITED STATES PATENT Ii oirrica LLOYD C. SWALLHQ', OF TEBRE HAUTE, INDIANA, ASSIGNOR TO COMMERCIAL SOLVENTS CORPORATION, OF TEBRE HAUTE, INDIANA, A COI BFPORATION OF MARYLAND HYDROGENATION OF CROTONALDEHYDE No Drawing. Original application filed November 7, 1927, Serial No. 2B1,781 D1vide d and this application filed September 16, 1929. Serial No. 393,128.

This invention is a process of making draining, and then rewa shing themv several butyraldehyde or butyl alcohol or both simultimes with cold distilled water. The. catalyst taneously, by the hydrogenation of crotonalis then again 'drled 1n the air at room dehyde. The process may be illustrated by temperature.

the following equations: I? thtifllilctllse of my proclessCi a mixturetpf Y cro ona e c e va or an 1 rogen 1n- 1e (1) g-Qfgi EEQQE proportion (if l'mo l of the foimer to'2 mols.

m H =CH QCH CH CHQ of the latter, is passed thru the catalyst at a butyraldehyde temperature of about 170 C. Under these 11) H conditlons the crotonaldehyde 1S completely iiitgriiicieh y O hydrogenated to form a mixture of about 2 H =CH .CH .CH .CHO parts of butyl alcohol to one part of butyralbltylalcohfl dehyde. When the mixture of crotonalde- In practice, when crotonaldehyde is hydrohyde and hydrogen is passed thru the cata- 15 genated the product usually contains butyrlyst at a rate of 1.7 g. crotona'ldehyde vaporaldehyde and butyl alcohol, the precise roized'per c. c. of catalyst per hour, the product portions of these ingredients being depen ent obtained contains less than 4% of high-b ilon a variety of factors such as the proportlon ing impurities. The productis recovered by of hydrogen present, temperature, space 'Vepassing the mixture leaving the catalyst thru 201 eity, and catalyst. an ordinary water condenser to liquefy it. '7

This invention relates to a process in which Under these conditions the effluent gas from an improved catalyst is used with the result the condenser is practically pure hydrogen. that a good conversion is obtained and only If the molecular proportion of .the reacting a small quantity of by-products is formedingredients is adjusted so that there is a 25 The by-produots ordinarily obtained 1n the large excess of hydrogen, for example, about hydrogenation are reaction products of butyr- 5 mols.'of hydrogen to 1 mol. of crotonalde-. aldehyde'either with itself or y with butyl hyde, the product obtained is about 90% alcohol. Butyl butyrate and dibutyl butylal butyl alcohol and 10% butyraldehyde. By Y are two by-products that-are ordinarily obincreasing the space velocity and using mo- :0 tained in rather lar e quantities, and one of lecular proportions of the reacting ingrethe advantages of t e present invention lles dients, one may'obtain aproduct which conin the prevention of the formation of subsists very largely of butyraldehydc. having 'stantial quantities of these impurities. only a small proportion of butyl alcohol.

In preparing acatalyst for use'in the'proc- VVhile- 170 C; has been described as the 5 ess, ordinary sodium silicate is diluted with optimum temperature for catalysis, the cata- 10 times its weight of distilled water. A lyst is active .over a wider range, and temper- 10% solution of copper nitrate is prepared atures between 120 and 200 C. maybe used. and is gradually added to the sodium-silicate In practise of the process it is not necessolution at ordinary temperature and with sary to make a preliminary reduction of the 49 constant stirring until precipitation is com. catalyst with hydrogen. The Washed gran-- 90 plete. The precipitate is then recovered ules may be used directly with good results.

from the mixture by filtration, using suction However, the activity of the catalyst is into remove as much 1i uid as possible. The creased if it is given a preliminary reduction resultant filter cake is ried in the air at ordiby passing pure hydrogen thru it at about nary temperatures until the material-sets to 350 C. and I prefer to follow this latter proform a rather hard, brittle mass. The mass cedure. The catalyst is preferably reduced is then pulverized and screened to produce in the apparatus in which it is later to be a catalytic material of about 8-14 mesh. used.

The granules are washed thoroughly by boil- In the preparation of the catalyst the re- 50 ing them with distilled water or an hour, action which occurs when copper nitrate is added to sodium silicate is presumed to produce copper silicate and sodium nitrate. The

sodium nitrate is soluble and is removed from the catalyst during the reliminary washing. It is quite possible tl fat during the preliminary reduction of the catalyst, if this is done, or during the first few moments of use in the process, the copper silicate catalyst may undergo some further chemical change. For example, a mixture of finely divided silica and copper may be the final result. In-.

deed it is possible that the primary reaction of copper nitrate and sodium silicate may produce a product comprising hydrated copper oxide and hydrated silicon dioxide, altho this is considered improbable. In place of copper nitrate, other salts of copper, such as the chloride or sulfate maybe used in the preparation of the catalyst. In any event, the

(ill

term' copper silicate as used in the appended claims is intended to describe and is limited to the reaction product of a soluble copper salt and sodium silicate as described in this specification.

This is a divisional application of my application U. S. Serial No. 231,781, for Hydrogenation of crotonaldehyde, filed November 7, 1927.

' Now having fully described my invention, I claim the following as new and novel:

1. A process for producing butyraldehyde and butyl alcohol which comprises passing a mixture of hydrogen and crotonaldehyde over a reduced copper silicate catalyst at a temperature of -120 C.

2. A process for producing butyraldehyde and butyl alcohol which comprises passing a mixtureof hydrogen and crotonaldehyde in molecular proportion over a reduced copper silicate catalyst at a temperature of about In testimony whereof I aflix my signature. LLOYD C. SWALLEN. 7

CERTIFICATE OF CORRECTION.

Patent No. 1,788, 89 Granted January 13, 1931,10

LLOYD C. SWALLEN.

It is hereby certified that error appears in the printed specification of theabove numbered patent requiring correction as follows: Page 2 line 35 claim 1, for "HO-120C" read 120-200C; and that the said Letters Patent should be read with this correction therein that the same may conform to the record of the case in the Patent Office.-

Signed and sealed this 3rd day of March, A. D. 1931.

M. J. Moore,

(Seal) Acting Commissioner of Pzitelits. 

